#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;
const int N = 105;
int a[N];
char s[N * 2];
int ans[N * 2];
int main() {
    int n, b;
    while (scanf("%d%d", &n, &b) != EOF) {
        memset(ans, 0, sizeof(ans));
        int l = 0;
        for (int i = 1; i <= n; ++i) {
            scanf("%s", s + 1);
            int l = strlen(s + 1);
            int t = l;
            for (int j = 201; j >= 201 - l + 1 && t >= 1; --j, --t) {
                int x;
                if (s[t] >= '0' && s[t] <= '9')    x = s[t] - '0';
                else if (s[t] >= 'a' && s[t] <= 'z')    x = s[t] - 'a' + 10;
                ans[j] = ans[j] + x;
                if (ans[j] >= b)    ans[j] %= b;
            }    
        }
        int i = 1;
        for (; i <= 201; ++i) {
            if (!ans[i] && i != 201)    continue;
            break;
        }
        for (int j = i; j <= 201; ++j) {
            if (ans[j] > 9) {
                int x = ans[j] - 10;
                printf("%c", x + 'a');
            }
            else printf("%d", ans[j]);
        }
        puts("");
    }
    return 0;
}